Mapping Literature with Networks: An Application to Redistricting

Understanding the gaps and connections across existing theories and findings is a perennial challenge in scientific research. Systematically reviewing scholarship is especially challenging for researchers who may lack domain expertise, including junior scholars or those exploring new substantive territory. Conversely, senior scholars may rely on longstanding assumptions and social networks that exclude new research. In both cases, ad hoc literature reviews hinder accumulation of knowledge. Scholars are rarely systematic in selecting relevant prior work or then identifying patterns across their sample. To encourage systematic, replicable, and transparent methods for assessing literature, we propose an accessible network-based framework for reviewing scholarship. In our method, we consider a literature as a network of recurring concepts (nodes) and theorized relationships among them (edges). Network statistics and visualization allow researchers to see patterns and offer reproducible characterizations of assertions about the major themes in existing literature. Critically, our approach is systematic and powerful but also low-cost; it requires researchers to enter relationships they observe in prior studies into a simple spreadsheet --- a task accessible to new and experienced researchers alike. Our open-source \textsf{R} package enables researchers to leverage powerful network analysis while minimizing software-specific knowledge. We demonstrate this approach by reviewing redistricting literature.

厘清现有理论与研究发现间的缺口与关联，始终是科学研究中的长期挑战。对于缺乏领域专业知识的研究者——包括青年学者或是探索全新研究范畴的人员而言，系统性梳理学术成果的难度尤甚。反之，资深学者则可能依赖长期沿袭的预设假设与社会关系网络，从而错失新兴研究成果。上述两种情形下，临时性文献综述均会阻碍知识的积累。学者在遴选相关既往研究，或是从研究样本中识别共性规律时，往往难以做到系统化。为推动形成系统化、可复现且透明的文献评估方法，本文提出一种易于上手的基于网络的学术成果梳理框架。在本方法中，我们将某一领域的文献视为由重复出现的概念（节点，nodes）以及这些概念之间的理论关联（边，edges）构成的网络。通过网络统计分析与可视化手段，研究者可清晰识别其中的研究规律，并对现有文献中围绕核心主题的各类论断实现可复现的特征刻画。尤为关键的是，本方法兼具系统性与高效性，且成本低廉：研究者仅需将其在既往研究中观察到的关联关系录入简单的电子表格中——这一任务无论对于青年研究者还是资深学者均易于完成。我们开发的开源R语言包可帮助研究者在无需掌握过多特定软件操作知识的前提下，运用功能强大的网络分析工具。本文以选区重划（redistricting）领域的文献梳理为例，对本方法进行了演示。